The modern age is the age of tablets and smartphones. With millions of devices with different screen sizes coming into the picture, making websites and UIs in a way that they fit on every one of those screens without having to separately code for every one of them is the only solution, as a web application that looks great just on PC won't do the trick.
Building mobile applications can likewise appear to be a nice option, however considering the colossal amount of various types of cell phones in the market, it's not a practical solution, but it is still superior to having no mobile apps at all!
Although It's possible to create mobile applications for prominent devices and platforms, it is absolutely not feasible for each app on the Play Store/App Store. Thus, for a site that works splendidly on each gadget, the only solution is 'responsive website design'. Additionally, with Google's latest MOBILEGEDDON, it will become essential to guarantee that your site is mobile-friendly, an area where only responsive web designing can help.
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